According to Wikileaks' website, "the leaks come from the accounts of seven key figures in the DNC." Those include Communications Director Luis Miranda, National Finance Director Jordan Kaplan, and Finance Chief of Staff Scott Comer. The emails stretch from January last year until this May.

Guccifer 2.0 claimed that these emails came from the same breach on the DNC, by simply responding: "yeah, u r a visionary, man."

Experts are sceptical about links between Guccifer 2.0 and this new dump of emails, though.

"The Wikileaks hacked #DNC emails feel qualitatively very different to the docs in the #Guccifer 2 hack," the information security expert known as Pwn All The Things tweeted. Over the last couple of months, Guccifer 2.0 has publicly released several caches of individual documents, but not full emails in this style.

When asked to prove whether he really was behind this latest dump, Guccifer 2.0 told Motherboard, "Why should I?" When pressed, he said, "just ask wikileaks guys." Wikileaks did not immediately respond to a request for comment.